Ellen D. Marcus

Recently recognized as a Litigation Trailblazer by the National Law Journal, and as a Virginia Lawyers Weekly “Go To” Lawyer, in both business litigation and business transactions, Ellen D. Marcus is civil trial lawyer with a proven track record of bringing business disputes to successful resolution for her clients, often after securing courtroom wins. She also advises clients who are starting new businesses or separating from existing ones. Having advocated for individuals and companies in business disputes for over 25 years, Ellen knows first-hand that having clear and well-thought-out agreements in the beginning can minimize the risk of costly litigation later on.   

For clients seeking Ellen’s advice and assistance, money, equity and control of a business tend to be at stake. On their behalf, in federal and state courts, and in arbitration proceedings, Ellen has successfully pursued and defended against claims of:  

• Breach of contract, including breach of partnership, operating, joint venture, employment, severance and non-disclosure (NDA) agreements,  

• Theft of trade secrets and confidential information,   

• Unlawful business conspiracy,   

• Tortious contract interference, and   

• Breach of fiduciary duties.    

CEOs, CFOs and other high-level employees who are in negotiations to join or separate from companies also seek Ellen’s advice and assistance.  These negotiations often result in employment and equity agreements, limited liability company (LLC) buyout agreements, and/or severance agreements.  Ellen has had many repeat clients over the years seeking these legal services at different points in the arc of their careers.  She treasures those and all of her client relationships.      

Before joining Holmes Costin & Marcus PLLC (now Costin Marcus PLLC) in Alexandria, Virginia in 2014, Ellen practiced law for 14 years in Washington, D.C. – most recently as a partner at Zuckerman Spaeder LLP.  At Zuckerman she learned from some of the country’s top trial lawyers and represented plaintiffs and defendants in courts throughout the United States.  Ellen crossed the river from D.C. to pursue her dream of having a Virginia-based firm catering to businesses and business people needing expert help in solving their business problems, both in and out of court.  

Ellen began her legal career as a law clerk for Judge Leonie M. Brinkema of the U.S. District Court for the Eastern District of Virginia.  She received her law degree from the Columbia School of Law, where she was a senior editor for the Columbia Law Review and a Harlan Fiske Stone Scholar. She received her bachelor’s degree in political science, magna cum laude, from Amherst College.